Method and system including renewable energy source and energy storage combined with turbine expanders for generating power

Abstract

Method and power generation system are provided. During a first mode of operation, an energy storage section (14) is arranged to store energy supplied by a renewable energy power source (12). A rotor shaft (16) axially connects a first turbine expander 18 and a second turbine expander (20). A first arrangement of blades (60) in expander (18) and a second arrangement of blades (62) in expander (20) relative to one another constitute a mirror image arrangement of one another. A combustor section (22) is fluidly coupled to mix a fuel and an oxidizer fluid to generate a flow of combusting fluid supplied to the turbine expanders to produce mechanical work during a second mode of operation. At least one of the fuel and the oxidizer fluid are based on at least some of the energy stored in the energy storage section.

Description

[0001] Method and System Including Renewable Energy Source and Energy Storage Combined with Turbine Expanders for Generating Power

[0002] TECHNICAL FIELD

[0003] [1] Disclosed embodiments are related to power generation, and more particularly, to method and power generation system with storage of energy from a renewable energy power source combinable with turbine expanders for generating power.

[0004] BACKGROUND

[0005] [2] The utilization of renewable natural resources (renewables) for energy generation in the last several years has been impressive, but there remain technical challenges to, for example, deal with the transient nature of the renewables. For example, both solar and wind power are intermittent by nature and, therefore, it is generally not feasible to provide, over an extended period of time, a steady baseload to power networks supplied by such renewables.

[0006] SUMMARY

[0007] [3] In one aspect, a power generation system includes a renewable energy power source. During a first mode of operation, an energy storage section is arranged to store energy supplied by the renewable energy power source. A turbine expander section includes a first turbine expander and a second turbine expander. A rotor shaft axially connects the first turbine expander and the second turbine expander to one another. The first turbine expander comprises a first arrangement of respective rows of blades and the second turbine expander comprises a second arrangement of respective rows of blades. The first arrangement of the respective rows of blades and the second arrangement of the respective rows of blades relative to one another constitute a mirror image arrangement of one another about the rotor axis. A combustor section is fluidly coupled to mix a fuel and an oxidizer fluid to generate a flow of combusting fluid supplied to the first turbine expander and the second turbine expander to produce mechanical work during a second mode of operation. At least one of the fuel and the oxidizer fluid are based on at least some of the energy stored in the energy storage section.

[0008] [4] In another aspect, a method for generating power comprises: during a first mode of operation, storing in an energy storage section energy supplied by a renewable energy power source; axially connecting by way of a rotor shaft a first turbine expander and a second turbine expander; arranging in the first turbine expander a first arrangement of respective rows of blades; arranging in the second turbine expander a second arrangement of respective rows of blades, where the first arrangement of the respective rows of blades and the second arrangement of the respective rows of blades relative to one another constitute a mirror image arrangement of one another about the rotor axis; and fluidly coupling a combustor section to receive a fuel and an oxidizer fluid and generate a flow of combusting fluid coupled to the first turbine expander and the second turbine expander to produce mechanical work during a second mode of operation, where at least one of the fuel and the oxidizer fluid are based on at least some of the energy stored in the energy storage section.

[0009] BRIEF DESCRIPTION OF DRAWINGS

[0010] [5] FIG. 1 through FIG. 5 are respective block diagram representations of respective example embodiments of disclosed power generating systems.

[0011] [6] FIG. 6 and FIG. 7 are respective schematic representations of first and second arrangement of rows of blades, where the first arrangement of blades and the second arrangement of blades relative to one another constitute a mirror image arrangement of one another about the rotor axis.

[0012] [7] FIG. 8 through FIG. 11 are respective schematic representations of respective example embodiments of turbine expanders and combustor sections that may be used in disclosed power generating systems.

[0013] [8] FIG. 12 is a flow chart of example steps of a disclosed method for generating power.

[0014] [9] FIG. 13 is a respective block diagram representations of one embodiment of a disclosed power generating systems in the context of a recuperated cycle application. DETAILED DESCRIPTION OF EMBODIMENTS

[0015]

[0010] FIG. 1 is a block diagram representation of one example embodiment of a disclosed power generating system 10 that includes a renewable energy power source 12, such as a wind turbine power source, a solar power source, etc. During a first mode of operation, an energy storage section 14 is arranged to store energy supplied by the renewable energy power source. For example, the first mode of operation will generally occur during times of low demand of power, e.g., low demand of power from power networks that may be connected to receive power from power generating system 10. That is, when surplus power from renewable energy power source 12 is available.

[0016]

[0011] In one example embodiment, power generating system 10 further includes a turbine expander section made up of a first turbine expander 18 and a second turbine expander 20 that are axially connected to one another by way of a rotor shaft 16. As can be appreciated in FIGs. 6 and 7, the first turbine expander comprises a first arrangement 60 of respective rows of blades and the second turbine expander comprises a second arrangement 62 of respective rows of blades. The first arrangement 60 of the respective rows of blades and the second arrangement 62 of the respective rows of blades relative to one another constitute a mirror image arrangement of one another about a rotor axis 63.

[0017]

[0012] In FIGs. 6 and 7, arrows 64 schematically represent respective axial thrust forces produced during rotation of the first and second arrangements 60, 62 of the respective rows of blades. Since the first and second arrangement 60, 62 of the respective rows of blades are both mounted onto rotor shaft 16 (e.g., FIG. 1), and thus the first and second arrangement 60, 62 jointly rotate about a common rotational direction, then the mirror image arrangement is effective to inhibit the magnitude of the net axial thrust forces resulting during rotation of the first arrangement 60 of the respective rows of blades and the second arrangement 62 of the respective rows of blades.

[0018]

[0013] As will be now appreciated by one skilled in the art, the foregoing mirror image arrangement defined by the first and the second arrangements 60, 62 is effective to reduce costs and / or enhance operational reliability of the turbine expander section, such as by way of eliminating thrust load bearings or extra thrust balance discs that otherwise could be needed without the mirror image arrangement of the first and second arrangement 60, 62 of the respective rows of blades.

[0014] In FIG. 6 the relative orientation of the first and second arrangements 60, 62 of the rows of blades allows conveying a working fluid (schematically represented by arrows 66) through the respective rows of blades from a central location of the first and the second arrangements 60, 62 to respective lateral locations. By way of comparison, in FIG.7, the reverse relative orientation of the first and second arrangements 60, 62 of the rows of blades allows conveying the working fluid (once again schematically represented by arrows 66) from the respective lateral locations to the central location of the first and the second arrangements 60, 62.

[0019]

[0015] Returning to FIG. 1, power generating system 10 further includes a combustor section 22 fluidly coupled to mix a fuel and an oxidizer fluid (e.g., air) to generate a flow of combusting fluid supplied to the first and second turbine expanders 18, 20 to produce mechanical work during a second mode of operation. As elaborated in greater detail below, at least one of the fuel and the oxidizer fluid are based on at least some of the energy stored in the energy storage section 14.

[0020]

[0016] For example, the second mode of operation will generally occur when power from renewable energy power source 12 is not available or is insufficient during times of high demand, and, in this mode, the flow of combusting fluid from combustor section 22 is expanded through the first and the second turbine expander 18, 20 to extract stored energy to produce electricity through one or more generators 30.

[0021]

[0017] FIG. 2 is a block diagram representation of another example embodiments of a power generating system 10. In this example embodiment, energy storage section 14 includes a compressor section 40 energized during the first mode of operation by renewable energy power source 12 to compress the air. In this example embodiment, energy storage section 14 further comprises a reservoir 42 fluidly coupled to store the air compressed by compressor section 40. Reservoir 42, without limitation, may be an airtight space, such as may involve natural caverns, mines, conventionally mined caverns, solution-mined caverns, aquifers, depleted oil and gas fields, and depending on the size of a given application, could include a plurality of storage tanks for storing the pressurized air.

[0022]

[0018] In this embodiment, during the first mode of operation (e.g., periods of low demand, etc.), surplus energy from renewable energy power source 12 is captured by compressing and storing the compressed air in reservoir 42 (by way of example the compressed air may be at any pressure suitable for the turbine expanders, such as in a range from approximately 15 bars to approximately 30 bars. The idea is to subsequently use the compressed air and a suitable fuel to generate energy during the second mode of operation, such as during times of higher demand. That is, the compressed air is drawn from reservoir 42, mixed with fuel, combusted, and then expanded through the first and the second turbine expanders 18, 20 to extract stored energy to produce electricity through one or more generators 30.

[0023]

[0019] FIG. 3 is a block diagram representation of still another example embodiment of a power generating system 10. In this example embodiment, energy storage section 14 comprises an electrolyser section 50 coupled to a source of water 52 and energized during the first mode of operation by renewable energy power source 12 to produce the fuel. That is, in this example embodiment, the fuel is generated using at least some of the energy supplied by the renewable energy power plant during the first mode of operation. Example fuels may be hydrogen, ammonia or any fuel that may be generated using the surplus renewable energy from renewable energy power source 12.

[0024]

[0020] FIG. 4 is a block diagram representation of yet another example embodiments of a power generating system 10. In this example embodiment, energy storage section 14 is a combination of the structural and / or operational relationships described above in the context of FIGs. 2 and 3. That is, energy storage section 14 includes compressor section 40 energized during the first mode of operation by renewable energy power source 12 to compress the air and store the compressed air in reservoir 42. In this embodiment, energy storage section 14 further includes electrolyser section 50 energized during the first mode of operation by renewable energy power source 12 to produce the fuel.

[0025]

[0021] FIG. 5 is a block diagram representation of yet still another example embodiment of a power generating system 10. In this example embodiment, energy storage section 14 is conceptually analogous to the embodiment described above in the context of FIG 4. In the example embodiment shown in FIG. 5, combustor section 22 is made up of two laterally disposed combustor sections compared to the singular centrally-disposed combustor section 22 shown in FIG. 4, where the centrally-disposed combustor section 22 is arranged between the first and the second turbine expanders 18, 20.

[0022] FIG. 8 is a respective schematic representation of one example arrangement of turbomachinery (e.g., turbine expanders 18, 20 and combustor section 22) that may be utilized in disclosed power generating system 10. For example, in this embodiment, combustor section 22 comprises a centrally-disposed combustor section 22 between the first and the second turbine expanders 18, 20. This example embodiment is conducive to advantageously reducing the axial length of rotor shaft 16 (e.g., FIG. 1) and in turn conducive to realizing a relatively compact of the involved turbomachinery.

[0026]

[0023] FIG. 9 is a respective schematic representation of another example arrangement of turbomachinery (e.g., turbine expanders 18, 20 and combustor section 22) that may be utilized in disclosed power generating system 10. For example, in this embodiment, combustor section 22, once again, is a centrally disposed combustor section 22 between the first and the second turbine expanders 18, 20. Because of substantial overlapping of components that make up the combustor section 22, such as combustor cans, this arrangement is conducive to even further reduction of the axial length of rotor shaft 16 (e.g., FIG. 1) compared to the example arrangement discussed above in the context of FIG. 8, and in turn realizing a relatively more compact integration of the involved turbomachinery.

[0027]

[0024] FIG. 10 is a respective schematic representation of still another example arrangement of turbomachinery (e.g., turbine expanders 18, 20 and combustor section 22) that may be utilized in disclosed power generating system 10. For example, in this embodiment, combustor section 22, once again, is a centrally-disposed combustor section 22 between the first and the second turbine expanders 18, 20. This arrangement involves radially-extending combustor cans, and this arrangement is also conducive to a relatively compact integration of the involved turbomachinery.

[0028]

[0025] FIG. 11 is a respective schematic representation of yet another arrangement of turbomachinery (e.g., turbine expanders 18, 20 and combustor section 22) that may be utilized in disclosed power generating system 10. For example, in this embodiment, combustor section 22 is made up of two laterally disposed combustor sections in lieu of a centrally-disposed combustor section between the first and the second turbine expanders 18, 20. This arrangement of the turbomachinery is believed to provide design flexibility in connection with the selection of the combustor components involved as well as the design of the combustor central casing. Additionally, this arrangement should provide user-friendly access for servicing of the respective combustor sections 22.

[0029]

[0026] It will be appreciated that one example embodiment of a disclosed power generating system involving a recuperated cycle application, as represented by way by the example embodiment shown in FIG. 13, is conducive to have a common heat exchanger 58 (e.g., recuperator) disposed in the region where a centrally-positioned exhaust 56 of the first and the second turbine expanders 18, 20 is located. By way of example, hot gas exhausted by turbine expanders 18, 20 is fluidly coupled into exhaust 56, where heat exchanger 58 is disposed. In this example embodiment, compressed air from compressed air storage 42 is fluidly coupled through heat exchanger 58 to extract thermal energy and then at least some of the compressed air with the extracted thermal energy is fluidly coupled to combustor section / s 22. It will be appreciated that in a general case, one or more heat exchangers 58 can be respectively connected to a respective exhaust of at least one of the first turbine expander 18 and the second turbine expander 20 58 to extract thermal energy and then at least some of the compressed air with the extracted thermal energy is fluidly coupled to combustor section / s 22.

[0030]

[0027] FIG. 12 is a flow chart of example steps of a disclosed method 100 for generating power. Subsequent to a start step 102, during a first mode of operation, step 104 allows storing in an energy storage section 14 (FIG.l) energy supplied by a renewable energy power source 12. Step 106 allows axially connecting by way of a rotor shaft 16 a first turbine expander 18 and a second turbine expander 20. Step 108 allows arranging in the first turbine expander a first arrangement 60 (FIG. 6 or FIG.7) of respective rows of blades. Step 110 allows arranging in the second turbine expander a second arrangement of respective rows of blades 62, where the first arrangement of the respective rows of blades and the second arrangement of the respective rows of blades relative to one another constitute a mirror image arrangement of one another about the rotor axis. Prior to a return step 114, step 112 allows fluidly coupling a combustor section 22 (FIG. 1) to receive a fuel and an oxidizer fluid and generate a flow of combusting fluid coupled to the first turbine expander and the second turbine expander to produce mechanical work during a second mode of operation, where at least one of the fuel and the oxidizer fluid are based on at least some of the energy stored in the energy storage section.

[0028] In operation, energy storage (e.g., surplus energy) from a renewable energy power source in combination with turbomachinery (e.g., turbine expanders) permits to subsequently utilize at least some of the stored renewable energy to produce electric power when power from the renewable energy power source, for example, is not available or is insufficient, such as during times of high demand.

[0031]

[0029] Although at least one exemplary embodiment of the present disclosure has been described in detail, those skilled in the art will understand that various changes, substitutions, variations, and improvements disclosed herein may be made without departing from the scope of the disclosure in its broadest form.

[0030] Unless otherwise stated, none of the description in the present application should be read as implying that any particular element, step, act, or function is an essential element, which must be included in the claim scope. The scope of patented subject matter is defined just by the allowed claims. Moreover, none of these claims are intended to invoke a means plus function claim construction unless the exact words "means for" are followed by a participle.

Claims

AMENDED CLAIMS received by the International Bureau on 04 February 2025 (04.02.2025)1. A power generation system comprising: a renewable energy power source (12); during a first mode of operation, an energy storage section (14) arranged to store energy supplied by the renewable energy power source (12); a turbine expander section comprising a first turbine expander (18) and a second turbine expander (20); a rotor shaft (16) to axially connect the first turbine expander (18) and the second turbine expander (20) to one another, wherein the first turbine expander (18) comprises a first arrangement of respective rows of blades (60) and the second turbine expander (20) comprises a second arrangement of respective rows of blades (62), wherein the first arrangement of the respective rows of blades (60) and the second arrangement of the respective rows of blades (62) relative to one another constitute a mirror image arrangement of one another about the rotor axis (63); and a combustor section (22) fluidly coupled to mix a fuel and an oxidizer fluid to generate a flow of combusting fluid supplied to the first turbine expander (18) and the second turbine expander (20) to produce mechanical work during a second mode of operation, wherein at least one of the fuel and the oxidizer fluid are based on at least some of the energy stored in the energy storage section (14).

2. The system of claim 1 , wherein the oxidizer fluid is air, and the energy storage section (14) comprises a compressor section energized during the first mode of operation by the renewable energy power source (12) to compress the air, wherein the energy storage section (14) preferably further comprises a reservoir fluidly coupled to store the air compressed by the compressor section.AMENDED SHEET (ARTICLE 19)3. The system of any one of the preceding claims, further comprising a power generating section connected to receive mechanical work produced by the first and the second turbine expanders (20) during the second mode of operation.

4. The system of claim 1, 2 or 3, wherein the energy storage section (14) comprises an electrolyser section (50) energized during the first mode of operation by the renewable energy power source (12) to produce the fuel, wherein the fuel is preferably selected from the group consisting of hydrogen and ammonia.

5. The system of claim 1, 2, 3 or 4, wherein the fuel is generated using at least some of the energy supplied by the renewable energy power plant during the first mode of operation, wherein the fuel is preferably selected from the group consisting of hydrogen and ammonia.

6. The system of any of the preceding claims, wherein the oxidizer fluid is air, and the energy storage section (14) comprises a compressor section energized during the first mode of operation by the renewable energy power source (12) to compress the air, wherein the fuel is generated using at least some of the energy supplied by the renewable energy power plant during the first mode of operation .

7. The system of any of the preceding claims, wherein the oxidizer fluid is air, and the energy storage section (14) comprises a compressor section energized during the first mode of operation by the renewable energy power source (12) to compress the air, wherein the energy storage section (14) further comprises an electrolyser section (50) energized during the first mode of operation by the renewable energy power source (12) to produce the fuel.

8. The system of claim 6 or claim 7, wherein the fuel is selected from the group consisting of hydrogen and ammonia, or wherein the system further comprising a power generating section connected to receive mechanical work produced by the first and the second turbine expanders (18, 20) during the second mode of operation .AMENDED SHEET (ARTICLE 19)9. The system of any one of the preceding claims, further comprising one or more heat exchangers (58) respectively connected to a respective exhaust of at least one of the first turbine expander (18) and the second turbine expander (20).

10. A method for generating power comprising: during a first mode of operation, storing in an energy storage section (14) energy supplied by a renewable energy power source (12); axially connecting by way of a rotor shaft (16) a first turbine expander (18) and a second turbine expander (20); arranging in the first turbine expander (18) a first arrangement of respective rows of blades (60); arranging in the second turbine expander (20) a second arrangement of respective rows of blades (62), wherein the first arrangement of the respective rows of blades (60) and the second arrangement of the respective rows of blades (62) relative to one another constituting a mirror image arrangement of one another about the rotor axis (63); and fluidly coupling a combustor section (22) to receive a fuel and an oxidizer fluid to generate a flow of combustion fluid supplied to the first turbine expander (18) and the second turbine expander (20) to produce mechanical work during a second mode of operation, wherein at least one of the fuel and the oxidizer fluid are based on at least some of the energy stored in the energy storage section (14).

11. The method of claim 10, wherein the oxidizer fluid is air, and the energy storage section (14) comprises a compressor section (40), the method further comprising energizing the compressor during the first mode of operation to compress the air, wherein the method preferably further comprising fluidly coupling the energy storage section (14) to a reservoir (42) to store the compressed air.

12. The method of any one of claims 10 through 11, further comprising connecting a power generating section to receive mechanical work produced by the first and the second turbine expanders (20) during the second mode of operation.AMENDED SHEET (ARTICLE 19)13. The method of claim 10, 11 or 12, wherein the energy storage section (14) comprises an electrolyser section (50), the method further comprising energizing during the first mode of operation by the renewable energy power source (12) the electrolyser section (50) to produce the fuel.

14. The method of claim 10, 11 or 12, further comprising generating the fuel using at least some of the energy supplied by the renewable energy power plant during the first mode of operation, or wherein the oxidizer fluid is air, and the energy storage section (14) comprises a compressor section (40) and an electrolyser section (50), the method further comprising, during the first mode of operation by the renewable energy power source (12), respectively energizing the compressor section (40) to compress the air, and the electrolyser section (50) to produce the fuel.

15. The method of claim 14, wherein the fuel is selected from the group consisting of hydrogen and ammonia or wherein the method further comprising connecting a power generating section to receive mechanical work produced by the first and the second turbine expanders (20) during the second mode of operation.AMENDED SHEET (ARTICLE 19)

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